This invention relates to medical devices and procedures used during the repair, replacement, or supplement of a medical patient's natural body organ structures or tissues. In particular, this invention relates to catheters with at least one integrated lumen for use in connection with such medical procedures and to methods of their manufacture.
Revascularization of the human heart is a good example of a medical procedure that involves the repair and supplement of a patient's body organ. Early procedures were known for revascularizing the human heart, but there were several disadvantages to these procedures. The earliest procedures involved exposing the heart by means of a midline sternotomy and stopping the beating of the heart to facilitate performance of the procedure. A graft is used to create a new, uninterrupted channel between a blood source, such as the aorta, and the occluded coronary artery or arteries downstream from the arterial occlusion or occlusions. Such a procedure has significant disadvantages, however, because it is highly invasive and requires general anesthesia. In fact, these disadvantages preclude the use of sternotomy procedures on many patients.
Less invasive procedures were later developed for revascularizing the heart, but these have disadvantages as well. For example, a thoracostomy involves surgical creation of ports in the patient's chest to obtain access to the thoracic cavity. Specially designed instruments are then inserted through the ports. Thoracostomy bypass procedures are less traumatic than sternotomy bypass procedures, but they are still too traumatic for some patients and may be inadequate when the number of surgical bypasses is large. Another procedure, which is known as a thoracotomy, revascularizes the human heart by gaining access to the thoracic cavity with incisions between the patient's ribs, but this procedure may still be too traumatic for some patients.
Goldsteen et al. U.S. patent application Ser. No. 08/745,618, filed Nov. 7, 1996, which is hereby incorporated by reference herein, discloses a less traumatic surgical technique for revascularizing the human heart. A key aspect of that invention involves the use of catheters that are inserted into a patient's body through relatively remote entry ports, such as a femoral (leg) artery of the patient, a brachial artery of the patient, or any other suitable entry point. Control of these instruments throughout their use is from a proximal portion that is outside the patient at all times. In order to minimize the number of entry ports or to perform any of the specialized surgical techniques disclosed therein, a single catheter instrument may include two or more lumens. However, as the number of lumens increases, conventional manufacturing methods may yield catheters that have outer diameters that are undesirably large, which may irritate sensitive vessels and preclude their use in narrow vessels. Furthermore, such catheters may be difficult to position and secure in a patient's body.
In view of the foregoing, it is an object of this invention to provide less traumatic methods and apparatus for revascularizing a patient.
It is another object of the invention to provide methods of manufacturing catheters with integrated lumens without substantially increasing the thickness of catheter walls.
It is still another object of the invention to provide a catheter that can create a hemodynamic seal when positioned across vessel walls.
It is yet another object of the invention to provide a catheter that can be positioned in a vessel and used to selectively secure one or more medical devices therein.